If you connect a device to the Surface's USB port or MiniHDMI port, Windows RT is good at detecting it and setting it up. However, I found its bundled driver list to be inadequate, and Windows Update often didn't find older printers' drivers even though Windows RT correctly identified the printer. Of course you can't install drivers directly from vendor websites because Windows RT prohibits any installations outside of Windows Update and the Windows Store.

The crux of the problem: Windows RT doesn't -- indeed, can't -- use Windows 7 drivers, so the huge catalog of drivers that Windows users have amassed over the years doesn't mean squat in the Windows RT world.

Some hardware manufacturers are bending over backward to get Windows RT drivers out the door, but they're trying to replicate a decade's worth of software in less than a year -- and every single one of those drivers, by definition, is "Version 1.0."

Take Hewlett-Packard, for example. Its Windows 8 driver list for HP LaserJets includes hundreds of drivers that work with Windows 8, but only a third of them work with Windows RT. Want to plug your trusty, cheap LaserJet CP 1210 into that brand-new Surfact RT tablet? Sorry, Charlie. It won't work -- at least, not until HP releases more drivers.

Dell's Windows 8 printer driver page lists Windows 8 drivers for more than 100 printers, but only a third of them have Windows RT support. Just two inkjet printers make the RT cut.

Canon's analogous site lists hundreds of printer models with Windows 8-compatible drivers, but fewer than half of the listed printers work with Windows RT. I could only find one group of Xerox printers with Windows RT support, the Xerox EX. Panasonic doesn't appear to have a similar list.

Microsoft changed the way it works with print drivers in Windows RT. There's a thorough explanation on the Building Windows 8 blog, but the key is this: "[We] have stopped shipping lots of printer drivers with Windows. Instead, we built a print class driver framework. This framework is extensible, as it supports printing to existing devices, but it also allows manufacturers to include support for new devices, even those that have not yet been designed."

The people writing the drivers not only have to contend with the inevitable changes in Windows itself, they need to learn an entire new programming interface: Version 1.0, not only for the drivers, but for the print class as well.

Only built-in webcams are compatible with Windows RT. USB-based webcams are not compatible with Windows RT.

Input devices like numeric keypads, trackball mice, and dictation microphones are not compatible with Windows RT.

iPods and iPads use a proprietary protocol that is not compatible with Windows RT and are thus not compatible with Windows RT.

Most USB-connected scanners are not compatible with Windows RT. Network-connected scanners are compatible with Windows RT.

Some day the Windows RT driver situation will be better than it is right now. In the interim, you'd better check with the manufacturer to see if a particular piece of hardware will work with Windows RT or not.

Woody Leonhard writes computer books, primarily about Windows and Office; he's currently working on the Win 10 follow-up to the thousand-page "Windows 8.1 All-in-One for Dummies." A self-described "Windows victim," Woody specializes in telling the truth about Windows in a way that won't put you to sleep.